Field of the Disclosure
This invention relates to the abatement of combustion of Li-ion batteries.
Description of the Related Art
U.S. Patent Publication 2014/0065461 discloses fluorinated materials for use in abating the combustion of Li-ion batteries. The fluorinated materials disclosed have different identities and different forms (states), i.e. solids and semi-solids. Various placements of the fluorinated material with respect to the Li-ion battery are disclosed, including placements in which multiple fluorinated materials are used. FIGS. 1, 2, 3, 4, and 5a, b, and c disclose placements outside the can of the battery, and FIG. 6 discloses placement of fluoropolymer film inside the metal foil enclosure of a prismatic type of Li-ion battery. Inside placement has the advantage of providing a combustion abatement effect closer to the source of overheating within the Li-ion battery, which can lead to combustion.
U.S. Patent Publication 2011/0262783 (assigned to Tesla) discloses the coating of the center pin in the region of electrochemical activity of a Li-ion battery in the jelly-roll configuration, the coating being an intumescent material, optionally having an overlayer of non-intumescent material. U.S. Pat. No. 8,309,240 discloses fire-retardant material encapsulated in a material that is electrochemically inert and then mixing the encapsulated spheres with the electrolyte or with the anode layer and/or the cathode layer of the Li-ion battery. Alternatively, fire retardant material is absorbed into the pores of a porous mandrel (center pin) and coated with the encapsulation material. Thus, the encapsulated fire-retardant material is installed in the region of electrochemical activity of the battery. The encapsulation material is disclosed to keep the fire retardant material out of contact with the electrolyte and electrodes until there is overheating which melts the encapsulation material, whereupon the fire-retardant material is released from the encapsulation.
There is a need for additional methods and Li-ion battery constructions that enable the fire retardant to be available inside the battery to abate combustion.